Your files stay on your Mac.
Convertessa reads your Hasselblad 3FR RAW files and renders them as WebP images — a modern, lossy-capable format widely supported across browsers and creative apps. The conversion runs entirely on your Mac; files never leave your machine. Set quality to tune the size-to-fidelity tradeoff, and convert one file or a whole folder in a single pass.
Drag one or more .3fr files into Convertessa, or point the CLI at a folder. Batch mode processes every 3FR file in the directory automatically.
Pick WebP from the output format list. Because WebP supports lossy encoding, you can also set quality here — higher values preserve more detail, lower values produce smaller files.
Click Convert. Convertessa decodes each RAW file at full resolution and writes the WebP output locally — no internet connection required, no data uploaded.
Images, audio, video, documents, archives and eBooks — all converted natively, right on your Mac.
Pick a format you have — see everything Convertessa can turn it into.
Convert hundreds of files at once with per-type group defaults and individual overrides.
First-class support for HEIC, AVIF and WebP — encode and decode, both ways. Read JPEG XL and a dozen more modern formats too.
Drop files anywhere on the window. Native, instant, and exactly what you’d expect on a Mac.
Dial in compression, resolution and bitrate. Keep originals pristine or shrink for sharing.
Never overwrite a file by accident. Convertessa appends safe suffixes automatically.
Every job is logged locally. Re-run a previous conversion or revisit recent outputs in a click.
Bundle your converted files straight into a single ZIP, TAR or 7z — packaged and ready to share the moment a job finishes.
Right-click any file in Finder and choose Convert. A Quick Action handles it on the spot — no need to open the app first.
Shrink Convertessa to a tidy mini window that tucks into a corner — just a drop zone and a format picker for quick, one-off conversions.
No cloud. No account. No upload. Every conversion happens entirely on-device, using the power already in your Mac. What you convert is nobody’s business but yours.
Script conversions, wire them into your build, or batch a folder from the terminal. The same engine, no GUI required.
Read the full CLI documentation →Shrink Convertessa down to a small, focused window — drop, convert, done, with your recent conversions one click away.
macOS 14+ · Apple Silicon & Intel
New formats, new features, and fixes — every release, on the record.
WebP is a lossy format, so some detail is traded for a smaller file size. Convertessa lets you set the quality level before converting — use a higher value to retain more detail, or a lower value to produce a smaller file.
Yes. Convertessa strips EXIF and embedded metadata from the output WebP file, so camera model, GPS coordinates, and shooting parameters are not carried over.
Yes. Drag a folder into Convertessa to batch-convert every 3FR file it contains, or run convertessa ./folder/ --to webp from the terminal.